Rubber composition

Patent metadata

Field	Value
Publication number	US-12371523-B2
Application number	US-202017786348-A
Country	US
Kind code	B2
Filing date	Dec 9, 2020
Priority date	Dec 17, 2019
Publication date	Jul 29, 2025
Grant date	Jul 29, 2025

Abstract

A rubber composition having an adhesion to a composition based on natural rubber, the composition being at least based on 5 to 95 phr of polyisoprene comprising a content by weight of 1,4-cis bonds of at least 90% of the weight of the polyisoprene; 5 to 95 phr of copolymer of ethylene and of a 1,3-diene of formula CH 2 ═CR—CH═CH 2 , the ethylene units in the copolymer representing more than 50 mol % of the monomer units of the copolymer, the symbol R representing a hydrocarbon chain having 3 to 20 carbon atoms; and a crosslinking system. Also disclosed is a tire, in particular a tire provided with a sidewall, comprising this composition.

First claim

The invention claimed is:

1. A rubber composition at least based on:
5 to 95 phr of polyisoprene comprising a content by weight of 1,4-cis bonds of at least 90% of the weight of the polyisoprene;
5 to 95 phr of copolymer of ethylene and of a 1,3-diene of formula (I), the ethylene units in the copolymer representing more than 50 mol % of the monomer units of the copolymer,
CH 2 ═CR—CH═CH 2   (I),

the symbol R representing a hydrocarbon chain having 3 to 20 carbon atoms; and

a crosslinking system.

2. The rubber composition according to claim 1 , wherein the copolymer contains ethylene units which represent between 50 mol % and 95 mol % of the monomer units of the copolymer.

3. The rubber composition according to claim 1 , wherein the copolymer contains units of the 1,3-diene of 1,2 or 3,4 configuration which represent more than 50 mol % of the units of the 1,3-diene.

4. The rubber composition according to claim 1 , wherein 1,3-diene is myrcene or β-farnesene.

5. The rubber composition according to claim 1 , wherein the copolymer has a glass transition temperature below −35° C.

6. The rubber composition according to claim 1 , wherein a content of the copolymer is within a range extending from 15 to less than 50 phr.

7. The rubber composition according to claim 1 , wherein the polyisoprene comprises a content by weight of 1,4-cis bonds of at least 98% of the weight of the polyisoprene.

8. The rubber composition according to claim 1 , wherein the polyisoprene is selected from the group consisting of natural rubber, synthetic polyisoprenes and mixtures thereof.

9. The rubber composition according to claim 1 , wherein the copolymer has a glass transition temperature between −90° C. and −35° C.

10. The rubber composition according to claim 1 , further comprising a reinforcing filler.

11. The rubber composition according to claim 10 , wherein the reinforcing filler comprises mainly carbon black.

12. The rubber composition according to claim 10 , wherein a content of reinforcing filler is within a range extending from 15 to 80 phr.

13. The rubber composition according to claim 1 , wherein a content of the polyisoprene is within a range extending from more than 50 to 85 phr, and a content of the copolymer is within a range extending from 15 to less than 50 phr, and further comprising a reinforcing filler comprising mainly carbon black.

14. A tire comprising the rubber composition according to claim 1 .

15. The tire according to claim 14 , wherein the rubber composition is present in at least one sidewall of the tire.

Assignees

• Michelin & Cie

Inventors

• Araujo Da Silva Jose-Carlos
• Lemerle Frederic

Classifications

• C08K3/04

  Carbon · CPC title

• C08F210/02

  Ethene · CPC title

• B60C1/0025 Primary

  Compositions of the sidewalls · CPC title

• C08F2500/27

  Amount of comonomer in wt% or mol% · CPC title

• C08F2500/32

  Glass transition temperature [Tg] · CPC title